President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president Barack revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret. (AP Photo/Carolyn Kaster)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret. (AP Photo/Pablo Martinez Monsivais)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret. (AP Photo/Pablo Martinez Monsivais)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret.(AP Photo/Pablo Martinez Monsivais)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president Barack revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret. (AP Photo/Pablo Martinez Monsivais)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president Barack revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret.(AP Photo/Pablo Martinez Monsivais)

President Barack Obama talks about national security, Thursday, May 23, 2013, at the National Defense University at Fort McNair in Washington. Declaring America at a "crossroads" in the fight against terrorism, the president Barack revealed clearer guidelines for the use of deadly drone strikes, including more control by the U.S. military, while leaving key details of the controversial program secret.(AP Photo/Pablo Martinez Monsivais)

AP10ThingsToSee - Solar Impulse, piloted by Andre Borschberg, takes flight during the second leg of the 2013 Across America mission, at dawn, Wednesday, May 22, 2013, from Sky Harbor International Airport in Phoenix. The plane's creators said the trip is the first attempt by a solar airplane capable of flying day and night without fuel across the United States. (AP Photo/Matt York)

Boy Scouts from right, Joey Kalich, 10, Steven Grime, 7, and Jonathon Grime, 9, raise their hands at the close of a news conference held by people against the change in the Boy Scouts of America gay policy Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting nearby are expected to address a proposal on Thursday to allow gay scouts into the organization. (AP Photo/LM Otero)

Boy Scouts from right, Joey Kalich, 10, Steven Grime, 7, and Jonathon Grime, 9, raise their hands at the close of a news conference held by people against the change in the Boy Scouts of America gay policy Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting nearby are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

Solar Impulse, piloted by André Borschberg, takes flight during the second leg of the 2013 Across America mission, at dawn, Wednesday, May 22, 2013, from Sky Harbor International Airport in Phoenix. The solar powered aircraft is scheduled to land at Dallas/Fort Worth International Airport on Thursday May 23. The plane's creators, Bertrand Piccard and Borschberg, said the trip is the first attempt by a solar airplane capable of flying day and night without fuel to fly across America. (AP Photo/Matt York)

The aircraft Solar Impulse is prepared for the second leg of the 2013 Across America mission, early Wednesday, May 22, 2013, at Sky Harbor International Airport in Phoenix. The solar powered aircraft is scheduled to land at Dallas/Fort Worth International Airport on Thursday May 23. The plane's creators, Bertrand Piccard and Borschberg, said the trip is the first attempt by a solar airplane capable of flying day and night without fuel to fly across America. (AP Photo/Matt York)

Solar Impulse, piloted by André Borschberg, takes flight during the second leg of the 2013 Across America mission, at dawn, Wednesday, May 22, 2013, from Sky Harbor International Airport in Phoenix. The solar powered aircraft is scheduled to land at Dallas/Fort Worth International Airport on Thursday May 23. The plane's creators, Bertrand Piccard and Borschberg, said the trip is the first attempt by a solar airplane capable of flying day and night without fuel to fly across America. (AP Photo/Matt York)

Former scout maser Mark Noel, of Hanover, NH, holds up a new merit badge of inclusion during a press conference at the Equal Scouting Summit being held near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

John Stemberger, center, leads a press conference backed by people against the proposed change in the Boy Scouts of America gay policy Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting nearby are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

Former Boys Scout leader Jennifer Tyrrell, left, rests her head on her son and current Boy Scout Cruz Burns, 8, before an news conference at the Equal Scouting Summit being held near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

Former Boys Scout leader Jennifer Tyrrell, center, is greeted as her son and current Boy Scout Cruz Burns, 8, bottom, looks on during the Equal Scouting Summit being held near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the Boys Scouts of America meeting are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

Boys Scout Alex Derr speaks out against anit-gay rules during the Equal Scouting Summit Press Conference being held near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. The boxes in front of Derr hold petitions calling for the Boy Scouts of America to end its anti-gay policies. (AP Photo/LM Otero)

Terri Hall, left, of San Antonio, Texas, stands with her son Nathaniel Hall, 8, as they hold signs near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the meeting are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)

Matthew Ray, 15, of North Richland Hills, Texas, holds signs near where the Boy Scouts of America are holding their annual meeting Wednesday, May 22, 2013, in Grapevine, Texas. Delegates to the meeting are expected to address a proposal to allow gay scouts into the organization. (AP Photo/LM Otero)